1. Field of the Invention
The present invention relates in general to a method of molding a foamed plastic article, and more particularly to a method of molding a skin-covered foamed plastic article, which comprises the steps of placing a skin member in a mold in a manner to intimately cover the wall of the cavity of the mold, pouring a liquid material of foamed plastic into the cavity, curing the material and removing a product, viz., a skin-covered foamed plastic article from the mold upon sufficient hardening of the material
2. Description of the Prior Art
In order to clarify the task of the present invention, one conventional method of molding a skin-covered foamed plastic article will be described with reference to FIGS. 4, 5 and 6 of the attached drawings.
Referring to FIG. 4 of the drawings, there is shown a seat 100 including a seat cushion 102 and a seatback 104 which are produced by the conventional molding method using such a mold 106 as shown in FIG. 6. As is seen from FIG. 5, which shows a cross section taken along the line V--V of FIG. 4, the seatback 104 (or seat cushion 102) comprises a foamed plastic 108 serving as a structural base of the seatback 104 and a skin member 110 intimately and integrally attached to the foamed plastic 108. The skin member 110 comprises an outer skin of cloth and an inner skin of wadding. As is seen from FIG. 5, the skin member 110 has two inwardly projected stitched portions 112a and 112b each extending along one side portion of the bag-shaped skin member 110. As is seen from FIG. 6, the mold 106 has a cavity 114 formed therein. Two longitudinally curved elongate ridges 116a and 116b extend along respective side walls of the cavity 114 to serve as skin member holders.
The conventional method of molding the seatback 104 (or seat cushion 102) is as follows:
First, the mold 106 is warmed to a predetermined temperature. Then, a skin member 110 in the form of a bag is put into the cavity 114 of the mold 106 with its mouth portion opened upward. Upon proper setting of the skin member 110 in the mold 106, the stitched portions 112a and 112b of the skin member 110 are suitably engaged with the two longitudinally curved elongate ridges 116a and 116b to assure positioning of the same with respect to the mold 106. Then, a liquid material of foamed plastic is poured into the cavity 114, and a lid 118 is placed on the mold 106, as is seen from FIG. 6. After a while, that is, after the material is cured or hardened to a certain level, a skin-covered foamed plastic article, viz., the seatback 104 is removed from the mold 106.
However, in the conventional method as described hereinabove, it is very difficult or at least troublesome to properly and tightly set the skin member 110 in the right position in the cavity 114 of the mold 106. In fact, during curing of the material in the mold 106, the stitched portions 112a and 112b of the skin member 110 would be disengaged from the ridges 116a and 116b due to vigorous foaming of the material therein. Of course, this causes deterioration in quality of the products.